Input devices, including touch sensor devices (also commonly called touchpads or proximity sensor devices), as well as biometric authentication devices, are widely used in a variety of electronic systems. Biometric authentication systems, such as fingerprint sensor devices, are used for authenticating users of devices. Among other things, biometric sensing technology provides a reliable, non-intrusive way to verify individual identify for authentication purposes.
Touch sensor devices typically include a sensing region, often demarked by a surface, in which the touch sensor device determines the presence, location and/or motion of one or more input objects, typically for purposes allowing a user to provide user input to interact with the electronic system.
Biometric authentication systems, such as fingerprint sensor devices also typically include a sensing region in which the fingerprint sensor device determines presence, location, motion, and/or features of a fingerprint or partial fingerprint, typically for purposes relating to user authentication or identification of a user.
Touch sensor devices and fingerprint sensor devices may thus be used to provide interfaces for the electronic system. For example, touch sensor devices and fingerprint sensor devices are often used as input devices for larger computing systems (such as opaque touchpads and fingerprint readers integrated in or peripheral to notebook or desktop computers). Touch sensor devices and fingerprint sensors are also often used in smaller computing systems (such as touch screens and/or separate sensing areas integrated in mobile devices such as smartphones and tablets).
In some circumstances, such as where minimizing power consumptions is a consideration, a touch sensor and/or fingerprint sensor may be operated in a low power mode and the device may execute a “wakeup” mode when an object is near the sensor. Some solutions utilize additional components and/or circuitry near the sensor to detect the presence of the object to initiate the wakeup.